Circuits provided with power electronics, which depending on the need can serve as rectifiers, as inverters or to convert alternating voltages of different frequencies into one another, are termed converters.
In the conversion from a three-phase network, for example from the three-phase domestic mains system, converters with six electronic switches are normally used. The employed electronic switches are the most expensive components in a converter circuit. Especially in equipment in which a plurality of electricity consumers have to be controlled via converters, the electronic switches constitute a significant cost factor. An example of the use of such equipment in the public sector is the disinfection of wastewater by means of UV radiation. If low-pressure radiators are used in this case, then in some cases more than 100 converters are necessary for large equipment.
There is therefore a need for inexpensive converters.
From patent specification AT 408 496 B a current converter operating as a rectifier of the isolating transformer-type converter is known, which is constructed with only two power transistors. Owing to the type of construction the efficiency for applications with a high energy requirement is unsatisfactorily low with this current converter.